Finding the Fourth Proportional to 9,904.80, 13,668.72 and 5,428.72

Step by Step Solution

1. Step 1: Write the proportion equation
   9,904.80 : 13,668.72 = 5,428.72 : x
2. Step 2: Convert to fraction form
   9,904.80/13,668.72 = 5,428.72/x
3. Step 3: Cross multiply
   9,904.80x = 13,668.72 × 5,428.72
4. Step 4: Simplify right side
   9,904.80x = 74,203,653.64
5. Step 5: Solve for x
   x = 74,203,653.64/9,904.80
6. Step 6: Final answer
   x = 7,491.69